Christmas always makes me reflect upon the great historic Christian doctrine of the Incarnation. As C. S. Lewis put it, “God became a man so that men could become sons of God.” The Advent season is a great time to explore the rich theology that stands behind the Christian view of Jesus’ two natures.

The biblically derived doctrine of the Incarnation (God in the flesh) stands at the very heart of historic Christianity. It teaches that the eternal Word, the second person of the Trinity, took unto himself a human nature and became man without in any way diminishing his deity (John 1:1, 14, 18; Philippians 2:5–6; Colossians 2:9; 1 John 4:1–3). Therefore, Christian orthodoxy views Jesus Christ as a single person who nevertheless possesses both a divine and a human nature. Those two natures (divine and human) find their union in the person of Christ (called the union). This understanding of the Incarnation led the early believers to refer to Jesus as the theanthropos (Greek: the “God-man”).

Some people today, however, think that the idea of Jesus possessing both a divine and a human nature is logically contradictory. They charge that Jesus’ human qualities and characteristics (the limits and boundaries of his human nature) cannot be connected with his divine qualities and characteristics (the unlimited and boundless character of his divine nature). This challenge stands as a potential obstacle to a person who is genuinely considering the truth-claims of historic Christianity.

I’d like to offer a way of viewing the union of Christ’s two natures that may help avoid this logical conundrum. I am posing this idea merely as a hypothetical way to resolve this challenge, not suggesting that this is the only, or even the best, way to respond to the issue. This is a venture into what I hope is a helpful form of speculative philosophical theology.

The Union of the Two Natures of Christ

Couldn’t Jesus have what amounts to a “special” human nature? That is, maybe Jesus’ human nature is both like and unlike the common, generic nature that the rest of humanity possesses. After all, while Jesus is fully human (like every other person) he is not solely human (unlike every other person). In other words, perhaps Jesus’ human nature is distinct from the typical nature that all people possess. In this way, Jesus holds a fully human nature that is still compatible with a person who is not solely human (also possessing a divine nature). The idea is to rethink the exact nature of Christ’s humanity without diminishing it.

If Jesus possesses a special human nature (call it “fully human plus”), then maybe he could suffer real limitations in time, space, and knowledge, yet the limited human nature would not conflict with his simultaneous possession of an unlimited divine nature. Accordingly, one could argue that the way in which Jesus was limited (special human nature) is in a different respect from the way in which he was unlimited (divine nature).

The law of noncontradiction asserts that two contradictory propositions cannot both be true at the same time and in the same respect. Formulated as I have stated it, the Incarnation (a fully human but not solely human nature that is uniquely compatible with a divine nature) wouldn’t necessarily violate the law of noncontradiction.

Of course, the doctrine of the Incarnation involves much divine mystery and my “fully human plus” theory also relies upon the miraculous creative power of God. Obviously, my brief venture into speculative philosophical theology definitely needs to be tested by Scripture, orthodox theological standards (creeds), and reason (1 Thessalonians 5:21).